bio unit 2 chemistry of life ch.6 vocab

acid

acid

substance that releases hydrogen ions when dissolved in water an acidic solution has a pH less than 7.

activation energy

minimum amount of energy needed for reactants to form products in a chemical reaction.

active site

specific place where a substrate binds on an enzyme.

adhesion

the attraction between 2 dissimilar phases.

amino acid

carbon compound joined by peptide bonds; building block of proteins.

atom

building block of matter; contains subatomic particles-neutrons, protons, and electrons.

base

substance that releases hydroxide ions when dissolved in water; a basic solution has a greater pH than 7.

buffer

mixture that can react with an acid or a base to maintain the pH within a specific range.

carbohydrate

organic compound containing carbon, hydrogen, and oxygen in a ratio of one oxygen and 2 hydrogen atoms for each carbon atom.

catalyst

substance that speeds up a chemical reaction by reducing the activation energy.

chemical bond

what holds atoms together in molecules.

chemical reaction

energy requiring process by which atoms or groups of atoms in substances are changed into different substances.

cohesion

the sticking together of particles of the same substance.

compound

pure substance with unique properties; formed when two or more different elements combine.

covalent bond

type of chemical bond formed when atoms share elctrons.

dehydration reaction

a chemical reaction in which a water molecule is eliminated from the reactant molecule.

electron

negatively charged particle that occupies the space around an atoms nucleus.

element

pure substance composed of only one type of atom cannot be broken down into another substance by physical or chemical means

enzyme

protein that speeds up a biological reaction by lowering activation energy needed to start the reaction

hydrogen bond

weak electrostatic bond formed by the attraction of opposite charges between hydrogen atom and an oxygen, fluorine, or nitrogen atom.

ion

atom that is negatively or positively charged because it has lost or gained one or more electrons.

ionic bond

electrical attraction between two oppositely charged atoms or groups of atoms.

isotope

two or more atoms of the same element having different number of neutrons.

lipid

hydrophobic biological molecule composed mostly of carbon and hydrogen that soil and waxes are lipids.

macromolecule

large molecule formed by joining smaller organic molecules together.

mixture

combination of two or more different substances in which each substance keeps its individual characteristics can have a uniform composition or have distinct areas of substances.

molecule

compound whose atoms are held together by covalent bonds

monomer

small molecules mostly organic that can join with other similar molecules to form very large molecules or polymers

neutron

particle without a charge in an atom's nucleus.

nucleic acid

complex macromolecule that stores and communicates genetic information.

nucleotide

a subunit of a nucleic acid formed from a simple sugar, a phosphate group, and a nitrogenous base.

nucleus

the central membrane-bound organelle that manages cellular functions and contains DNA.

peptide bond

a covalent bond formed by joining the carboxyl group of one amino group of another with the removal of a molecule of water.

pH

the concentration of hydrogen ions in a solution.

polar molecule

molecule with oppositely charged regions.

polymer

large molecule formed from smaller repeating units of identical or nearly identical compounds linked by covalent bonds.

product

substance formed by a chemical reaction located on the right side of the arrow in a chemical equation.

protein

organic compound made of amino acids joined by peptide bonds primary building block of organisms.

proton

positively charged particle than an atom's nucleus.

reactant

substance that exists before a chemical reaction starts located on the left side of the air when a chemical equation.

solute

substance dissolved in a solvent.

solution

homogeneous mixture formed when a substance (solute) is dissolved in another substance (solvent).

solvent

substance in which another substance is dissolved.

substrate

reactant to which an enzyme binds.

van der waal's force

attractive forces between molecules.